This invention relates to magnetically actuated switches of the type having a carrier with switch contacts on one side thereof which are selectively bridged by a movable conductive armature. The armature's movement into and out of shorting relation with the spaced contacts is governed by a coupler mounted for movement on the opposite side of the carrier. One of the coupler and armature is a magnet and the other is made of magnetic material. By magnetic material it is meant that the material is affected by a magnet. Thus, the armature is magnetically coupled to the coupler and generally moves therewith to either short or open the switch contacts.
Switches of this general nature are shown and described in U.S. Pat. Nos. 5,666,096 and 5,523,730 and U.S. Pat. No. 5,867,082 and U.S. patent application Ser. No. 09/160,645, filed Sep. 28, 1998, the disclosures of which are hereby incorporated by reference. The present invention is an extension of this technology in the area of pushbutton switches.
One of the advantages of magnetically actuated switches is that switch closure can be effected with very little travel of the movable parts. In some applications, however, it is desirable to allow full travel of an actuator even though only a minor portion of the full travel is needed to close the switch. For example, users of some consumer products, through long experience with conventional full travel switches, come to expect a particular type of switch actuator. Manufacturers often find it preferable to accommodate that expectation rather than try to retrain consumers to accept a switch with minimal travel. Other switches may require relatively large actuators so they can be found and manipulated more or less by touch rather than visually. Automobile dashboard controls are an example.
Another difficulty in switch design is combining multiple switches in a single actuator. Combination switches are desirable to eliminate clutter and minimize the size of control panels. Applications such as automotive sound systems utilize combined rotary and pushbutton switches to control volume and display functions (e.g., time of day or selected radio frequency), respectively. The mechanical requirements of making and breaking two sets of contacts with one actuator typically result in complex, and therefore expensive, switch designs.